Here's a childhood favourite:
You probably know it's from the 1964 Disney movie version of "Mary Poppins," but did you know it was the subject of a lawsuit based on earlier song title "Supercalafajalistickexpialadojus"(1949)? Known as "The Super Song," it was recorded by Alan Holmes and his New Tones, lyrics by Patricia Smith (a Gloria Parker pen name. She was the one suing Disney.)
Disney won in the end, because they showed that variants of the word were in use well before 1949.
The word was added to the Oxford English Dictionary in 1986.
Some people have tried to break it into parts:
but that doesn't make any sense, I think.
Maybe it's best to just enjoy it for the wonderful nonsense it is?
Here's a link to the Disney version on Youtube. Go on, listen to it. It's the song equivalent of chugging a can of Red Bull.